如何遍历函数并将每个用户添加到字典中？ （使用psutils包）

Question

I'm using a package called psutils which lets me get some usage information of users on my platform (RHEL7 box). The main ones I care about are CPU and Memory, which it does great.

I am able to put in a user id, and get their memory usage based on the package's functions that describe in their documentation (and then doing some math on my own to customize it).

I also am able to do a basic loop of all the users currently logged in and get a list of them.

I'm struggling on trying to combine both of that - ie loop through all of the users, apply the function to each one to get all of their memory usage.

Currently, my code is setup to run 1 user at a time - ie I can search for myself (Rob) and it will spit my memory out. Now I'm trying to have it loop through all of them.

If it helps here are my 2 working, very separate chunks of code:

Using PSUTILS to find 1 user at a time memory

(For example, me as the user, user=rob)

import psutils
import os

mem = psutil.virtual_memory()

#Get all processes for the user (except this one!)
procs = [p.memory_info().rss for p in psutil.process_iter() if p.username() == user and p.pid != os.getpid()]
user_mem = sum(procs)
user_procs = len(procs)
percent_total = user_mem / mem.total * 100

And then I can see my memory simply with something like

print(user_mem)

And I'll see (some large number as its in bytes)

1XXXXXXX

However, that's just for me - I could supply a list of all the users and run through it all but I don't know if all of them are logged in at that time.

I found a function in psutils, psutils.users() which returns a list of all the users currently logged in.

Using PSUTILS to get a list of all users

If I run:

psutil.users()

I'll get a list like:

    [suser(name='person1', terminal='pts/0', host='XX.XXX.XXX.XXX', started=1521547648.0),
 suser(name='person2', terminal='pts/3', host='XX.XXX.XXX.XXX', started=1521625856.0),
 suser(name='person3', terminal='pts/6', host='XX.XXX.XXX.XXX', started=1521737728.0),
 suser(name='person4', terminal='pts/7', host='XX.XXX.XXX.XXX', started=1521742080.0),
 suser(name='person5', terminal='pts/1', host='XX.XXX.XXX.XXX', started=1521729920.0),
 suser(name='person6', terminal='pts/8', host='XX.XXX.XXX.XXX', started=1521721472.0),
 suser(name='person7', terminal='pts/11', host='XX.XXX.XXX.XXX', started=1521721472.0),
 suser(name='person8', terminal='pts/14', host='XX.XXX.XXX.XXX', started=1521550208.0),
 suser(name='person9', terminal='pts/18', host='XX.XXX.XXX.XXX', started=1521731328.0),
 suser(name='person10', terminal='pts/22', host='XX.XXX.XXX.XXX', started=1521730688.0)]

So the problem I'm having now is figuring out a way to grab all of those users and apply the my code above and have each one get their memory usage.

Then from there, I'm sure I'll able to figure out the maximum, highest user on my own.

But I currently am very lost on trying to get that dictionary of all of the users with the values of each of their memory.

Answer 1

Sounds like all you need is to .map on the output of psutil.users() . Create a function that takes a suser , filters psutil.process_iter() the same way you are doing it now for that user, and returns the values you care about.

ps_users = [suser(name='person2',...)]

def get_memory_for_user(user):
    procs = [p.memory_info().rss
       for p in psutil.process_iter()
       if p.username() == user.name and p.pid != os.getpid()]
    return (user.name, sum(procs), len(procs,)

users_usage = map(get_memory_for_user, ps_users)

Answer 2

This should get you on the right track but I'd create a dictionary and store the users there to iterate through. One thing to note, from running psutil.users() on my system, I see my username listed multiple times for each tty. You'll want to look into if procs is getting all of those.

Anyway the code should roughly look like:

import psutils
import os

mem = psutil.virtual_memory()

ps_dict = {}

for u in psutil.users():
    ps_dict[u].name = None

for user in ps_dict.keys():
    #Get all processes for the user (except this one!)
    ps_dict[user] = {
        'procs':[p.memory_info().rss for p in psutil.process_iter() if p.username() == user and p.pid != os.getpid()],
        'user_mem' : sum(procs),
        'user_procs' : len(procs),
        'percent_total' : user_mem / mem.total * 100
        }